1. Technical Field
This invention relates to improvements in the feeding of sheet material such as paper sheets in an offset printing machine and more particularly to an adjustable sheet register controlling mechanism.
2. Description of the Prior Art
Paper sheet feed apparatus for offset printing machines and the like have been disclosed in the following U.S. Pat. Nos. 2,085,592, 3,169,018, and 4,146,217. These patents show sheet pick up devices which are relatively fixed and require shutting down the printing machine and making a mechanical adjustment in the feed linkage in order to accommodate paper sheets of differing weights, thickness, stiffness, and flexibility of the paper. This invention enables an operator to vary the registration of a plurality of vacuum shoes in the printing machine with a sheet of paper with respect to one end thereof whereby adjustment of the device enables the operator to position the vacuum shoes registry with the top sheet of paper at a desirable location with respect to the entry grippers or the printing roll feed.